Jewish "Filth"

First, it was Mahmoud Abbas.

He said

"The Al-Aqsa [Mosque] is ours... and they have no right to defile it with their filthy feet. We will not allow them to, and we will do everything in our power to protect Jerusalem."

He was repeating an earlier canard officially promoted by the Palestinian Authority:

Jews praying at Western Wall are "sin and filth"

Then, it - you should pardon the expression - spread.

As far as to ... Canada:-

Ayman Elkasrawy, a teaching assistant at Ryerson University who in a sermon preached “purify the al-Aqsa Mosque from the filth of the Jews,” has been dismissed by the university.
In a letter to B’nai Brith Canada, Ryerson President Mohamed Lachemi noted that Elkasrawy was “no longer employed by the university,” and added that “we remain actively engaged in addressing antisemitism in our community.” B’nai Brith had sent a letter demanding that Elkasrawy be fired on Feb. 21.Elkasrawy, who worked within Ryerson’s Faculty of Engineering and Architectural Science, delivered his inflammatory supplications at the Masjid Toronto in June of 2016. The mosque later issued an apology for his remarks.

Thinking those thoughts and pronouncing them and teaching them is just, well, filth.

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